Standard Accessories
- 4 Bidirectional wheels
- 2 Grounding terminals
- 1 Identification plate
- 2 or 4 lifting lugs (according to the Rating Power)
- 4 Connections for haulage
- Tapping Terminal board on MV side
- Threaded Pins provided with bolt for MV terminal connection
Accessories on Request
Different types of accessories are available in SEA Transformers Product Portfolio.
The main are the following:
Safety Devices
1. Oil Temperature Indicator
Where is used: All types of Transformers
Description:
Device used to measure the top oil temperature in the tank by a sensor.
It can be provided with 2 or 4 SPDT switches.
2. Winding Temperature Indicator
Where is used: All types of Transformers
Description:
Device used to measure the winding temperature in the Liquid Immersed Transformers by indirect way.
It can be provided with Max 4 SPDT switches.
3. Buchholz Relay
Where is used: Transformers with Conservator
Description:
Such device intercepts and collects any gas bubble coming from the inner side of the transformer and/or signals any oil leakage from the tank (that indicates schort circuit or other faults).
There are different options according to the dimension of the pipe connecting flange.
It is suitable also a Gas Sampling Device connected with Buccholz Relay if it is necessary to collect the gas for the testing analysis.
4. Air Breather
Where is used: Transformers with Conservator
Description:
The aim of such device is absorbing the humidity air that the transformer sucks during the thermal contraction of the liquid in order to guarantee a better dielectric capacitance.
There are different dimension and connections according to the oil contained in the conservator; when the salt becomes green means it is satured by humidity.
5. Oil Level Indicator
Where is used: Transformers with Conservator
Description:
Such device gives a visual signal of the oil level in the conservator.
There are different options according to the dimension of the conservator; it is also possible to signal the MAX and/or MIN oil level by switches.
6. Pressure Relief Device
Where is used: Transformers with Conservator (smaller PRD without contacts can be available also for Hermetic Transformers)
Description:
In case of sudden and violent internal short circuit the insulating liquid produces a large volume of gas that should be evacuated in order to avoid the explosion of the transformer. By PRD it possible to evacuate the oil.
There are different dimensions according to the oil quantity contained inside the tank of the transformers; it is also possible signals the opening of the PRD by switches placed on the cover
7. DGPT2 or RIS
Where is used: Hermetic Transformers
Description:
Device used for keeping under control Oil Pressure, Temperature and Oil Level of the liquid inside the transformer tank.
8. Shutter Valve
Where is used: Power Transformers with Conservator
Description:
Device used to block the escape of oil coming from conservator in case of leakage in the transformer tank.
It is interposed between Buchholz relays and the conservator.
Can be set with with an alarm and trip signal according to the flow valve setting.
9. Flow Indicator
Where is used: Power Transformers with Conservator
Description:
Device used to control of the oil flow out of the pumps on transformers with forced oil cooling equipment.
It is used also in water cooled transformers.
Are also available small flow indicator for Distribution Transformers.
10. Antivibrating Pads
Where is used: Distribution Transformers
Description:
Rubber supports to be assembled under the wheels in order to reduce the noise and structural resonances.
11. Marshalling Box
Where is used: Distribution Transformers
Description:
It allows a strong reduction of the capacitive coupling between MV and LV winding and also a reduction of overvoltages transferred among the same windings.
12. Overvoltage Protection Devices
Where is used: All type of Transformers
Function:
The aim is to protect the regulating winding.
There are two possibility:
using Surge Arresters located close to the terminals as possible or using Spark Gaps on the bushings.
Electronic Safety Devices
To have an instant control on all essential parameters of the transformer, SEA can provide part of the accessories with
ANALOG OUTPUT 4÷20 mA
or
RS485 DIGITAL OUTPUT MODBUS PROTOCOL
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Contact our sales dept. for adding information regarding which types of accessories can have such function.
Bushings
13. Elastimold Bushings
Where is used: Distribution Transformers
Description:
The plug connection allows a very rapid connection of the cable to the transformer and can be touched when the transformer is under voltage.
They are manufactured according to the Standards: EDF HN 52 S 61 - CENELEC EN-50181-50180 - IEEE 386-1995 - UTE C 66-555 - DIN 47636.
Always specify the type of rapid connection desired.
(contact our sales dept. for adding information)
14. Busbars
Where is used: Distribution Transformers
Description:
Suitable for indoor and outdoor application with protective cap.
They are manufactured according to the Standards: EN 50387, ENEL DJ1107-1109 and BS 2562/1979.
15. Inner Cone Bushings
Where is used: Distribution Transformers
Description:
Suitable for indoor and outdoor application with protective cap.
They are manufactured according to the Standards: DIN 47637 - ENEL DJ1111 and DJ1108.
16. Porcelain Bushings
Where is used: All type of Transformers
Function:
Oil to air bushings used to bring the connection from the transformer insulation medium to the external insulation medium.
Suitable for Voltages up to 45 kV.
17. Composite Bushings
Where is used: All type of Transformers
Function:
Oil to air bushings used to increase general safety level it is possible to use such bushings made of composite material instead of porcelain in order to guarantee no oil leakages, no risk of fire, possibility to be assembled horizzontally and control of partial disharges.
They are interchangeable with porcelain Bushings in compliance to EN 50180 Standard and suitable for use according to C5 corrosiveness class with reference to ISO 12944.
Remark: such bushing is not a condenser bushing but can give the signal of the voltagevia a capacitive socket.
18. Condenser Bushings
Where is used: Power Transformers
Description:
Bushings suitable for voltages from 25 to 52 kV or higher.
It is possible to get an active control of voltage distribution between the central high voltage lead and the external flange.
19. High Current Bushings
Where is used: Power Transformers
Description:
Bushings up to 30 kA.
Their aim is conduct heat by the central massive conductor.
Cable Boxes
Where is used: Distribution Transformers
Description:
Boxes used to protect bushings according to IP Classification.